1. Technical Field
The present invention relates generally to valves for fluid control valves and more particularly to valve devices and methods flow liquid product and propellant gas in a liquid product dispensing device.
2. Background Art
Devices for dispensing liquids are generally known in the art. Such conventional devices generally include a container for storing a liquid product and a means for ejecting the liquid product from the container through a dispensing head or a nozzle. Such conventional delivery means often include a reservoir of pressurized gas stored in the container. The pressurized gas serves as a propellant for forcing the liquid product out of the container.
Such conventional devices often include a dispenser head including a depressible pump or actuator for manual manipulation by a user. By depressing the dispenser head, a user may selectively open a valve or other mechanism that allows the pressurized gas, or gas propellant, to force the liquid product through the valve and out of the dispensing head for application or use. Such conventional devices are commonly used to store and dispense liquid products including cosmetic products. A cosmetic product, or a cosmetic liquid, may be referred to as a hair spray, a deodorant, a foam, a gel, a coloring spray, a sunscreen, a skin care agent, a cleaning agent or the like.
In some applications, it is generally desirable to provide a dispensing device for a liquid product, such as a cosmetic product, that achieves an atomized spray of the liquid product upon ejection from the dispensing device. Generally, it is preferable to provide an atomized spray of fine particles that are relatively small and uniformly sized. Conventional dispensing devices for delivery of cosmetic products are inadequate because such devices do not provide a uniform dispersion of atomized particles having optimal small sizes. Instead, conventional dispensing devices often provide atomized liquid dispersions or sprays that include non-uniformly sized particles.
Another problem associated with conventional dispensing devices for liquid products includes clogging of the channels in the dispensing device. For example, it is generally known in the art that atomized sprays can be generated to include smaller particles by providing a smaller diameter orifice at a spray nozzle exit. However, by reducing the dimensions of the spray nozzle exit, the more likely it is that the exit orifice will become clogged by the liquid product. This is especially true for liquid products that have adherent properties, such as cosmetic products, hair sprays, skin sprays, fragrance sprays, deodorant sprays, paints, glues, pesticides, etc.
In order to overcome the problems associated with conventional devices and methods for delivering a liquid product from a dispensing device as an atomized spray, it may be necessary to initiate the flow of gas prior to initiating flow of the liquid product and to also terminate flow of liquid prior to termination of flow of gas. However, conventional delivery valves do not provide such sequential delivery and termination of liquid product and gas propellant.
What is needed then are improvements in valve devices and methods for sequential delivery of liquid products and gas propellants in the form of an atomized spray.